1. Field of the Invention
The present invention relates to a system for measuring a distance to an object of distance measurement and more particularly to an active distance measurement system favorably applied to various types of cameras.
2. Related Background Art
Such an active distance measurement system applied to cameras generally includes an infrared-emitting diode (IRED) for emitting a beam of light toward an object of distance measurement, and a position sensitive detector (PSD) for receiving the emitted and reflected light beam. The signal outputted from the PSD is processed in signal processing and arithmetic circuits to be inputted therefrom as distance information into a central processing unit (CPU), by which a distance to the object of distance measurement is determined. Because an error may occur in distance measured based on one-shot light emission alone, multi-shot light emissions are generally performed thereby to obtain multiple pieces of distance information. The obtained information is typically integrated and averaged in an integrating circuit.